Submission #875418

#	Time	Username	Problem	Language	Result	Execution time	Memory
875418		vjudge1	Sjekira (COCI20_sjekira)	C++17	110 / 110	42 ms	13140 KiB

sjekira

#include<bits/stdc++.h>
using namespace std;
const int N=1e5+7;
#define int long long
#define fi first
#define se second
typedef pair<int, int> ii;
int n;
ii w[N];
vector<int> g[N];
int p[N], ma[N], sz[N], ans=0, cx[N];

int Find(int u){
    if(u==p[u]) return u;
    return p[u]=Find(p[u]);
}

void Merge(int a, int b){
    a=Find(a); b=Find(b);
    if(a!=b){
        if(sz[a]>sz[b]) swap(a, b);
        p[a]=b;
        sz[b]+=sz[a];
        ans=(ans+ma[a]+ma[b]);
        ma[b]=max(ma[b], ma[a]);
    }
}

int32_t main(){
    cin.tie(0)->sync_with_stdio(0);
    cin>>n;
    for(int i=1; i<=n; i++){
        cin>>w[i].fi;
        w[i].se=i;
    }
    for(int i=1; i<n; i++){
        int x, y;
        cin>>x>>y;
        g[x].push_back(y);
        g[y].push_back(x);
    }
    for(int i=1; i<=n; i++) ma[i]=w[i].fi;
    sort(w+1, w+n+1);
    for(int i=1; i<=n; i++){
        p[i]=i;
        sz[i]=1;
    }
    cx[w[1].se]=true;
    for(int i=2; i<=n; i++){
        for(int j: g[w[i].se]) if(cx[j]) Merge(w[i].se, j);
        cx[w[i].se]=true;
    }
    cout<<ans;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 30 / 30
• Subtask 4: 60 / 60